My customers not showing up in Manage Store Credit

I’m trying to add Store Credit to a few past customers. The customers (name and email address) is showing up in the WooCommerce>Customers section. However, when I search for name or email address in Coupons>Manage Store Credits>Customers, they don’t show up (so I can’t add credit to them).

It’s strange, there are 1500+ Customer entries in the “Manage Store Credits” section … but none of the 20 customers I just searched for.

If they are in WooCommerce>Customers (which they are) … shouldn’t they show up here?

The page I need help with: [log in to see the link]